1. What is most likely lens that is missing, in regards to standard available lenses of the time? I am having a hard time finding any lens in that focal range that is set in a leaf shutter.
2. Would it more likely have been a barrel lens in this focal length?
3. To the best of my knowledge and research, Kalart rangefinders of this vintage can only be adjusted to one lens at a time and it is a less than speedy process to change a lens and re-align the rangefinder to the new focal length, so what was the preferred way to quickly swap lenses and start shooting again?
I saw one board posting on another site that outlined a process whereby you continue to use the range finder calibrated to your "normal" lens settings, but then note the distance on focus scale #1 and transfer it to focus scale #2 (the 2nd lens), but this seems a bit imprecise.